David Ginsburg has served over 20 years as a math teacher, instructional leader, and PD provider. He leads a Philadelphia-based team of consultants that specializes in instructional coaching, leadership coaching, and common-core implementation. Follow David on Twitter, and connect with him through email and LinkedIn.

I never worked harder in or out of the classroom than I did when preparing and presenting two lessons per class. Yet despite my diligence, ability grouping was ineffective, as reflected in students' actions and words: "You are too bogus Coach G. You know Group A is not that smart and Group B is smart, and you separate us so we look dumb. All of us should be in the same group to help each other out."

Are you overwhelmed trying to navigate the sea of sites related to Common Core Math? Here's a manageable list of free online resources my team has found helpful in our Common Core Math work with instructional leaders and teachers.